Injection device with sealed luer fitting

ABSTRACT

The invention relates to an injection device ( 110 ) with a luer fitting. The injection device has a compressible syringe body ( 137 ) defining a reservoir ( 146 ). A male luer fitting ( 150 ) has a channel ( 152 ) therethrough for conducting contents of the reservoir, and a luer tip at an end of said male luer fitting opposing said base end. A first connecting structure ( 182 ) is arranged on said male luer fitting between said base end and said luer tip. A shield cap ( 160 ) is arranged on the male luer fitting. The shield cap has a second connecting structure interacting with said first connecting structure to prevent inadvertent movement of said shield cap relative to said male luer fitting when said shield cap is arranged at said first position. A first seal ( 170 ) is provided for sealing said channel at said luer tip. A second seal ( 180 ) is arranged between said shield cap and said male luer fitting for sealing the outer surface and the luer tip of said male luer fitting from outside contamination.

PRIORITY CLAIM

This is a U.S. national stage of application No. PCT/US2009/004120,filed on Jul. 15, 2009, the content of which is incorporated here byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a prefilled injection devicefor delivering a dose of medicament by injection and having a sealingsystem for preventing contamination of the injection device prior to itsusage. More particularly, the present invention is directed to a syringeassembly including a sealed luer fitting.

2. Description of the Related Art

Syringes used for the delivery of medicaments to patients are wellknown. Oftentimes syringes are prefilled with a dosage of a medicamentor other substance by a pharmaceutical manufacturer and then distributedto end users such as health care professionals or patients foradministration of the prefilled dosage of medicament.

A “compression syringe” used herein refers to a syringe which holdsmedicament in a reservoir defined by walls with at least one beingcompressible when squeezed by a user's hand. Compression syringes can beprefilled with a single dose of the medicament, which can be expelledout from the reservoir upon compressing the reservoir. Because of theirlightweight and compact properties, their ruggedness and low cost,compression syringes are widely used in many circumstances.

U.S. Pat. No. 4,955,871 discloses a compression syringe 10; the entirecontent of the U.S. patent is hereby incorporated by reference. As isdepicted in FIGS. 1 to 3, a conventional compression syringe 10 has aneedle assembly for injecting the medicament into the patient. Theneedle assembly includes a needle cannula 12 passing through andfastened in a needle hub 20. The needle assembly also includes a nozzle18 having a closed end connected to an injection port and an open endfor holding the needle hub 20. The closed end of the nozzle 18 is formedby a nozzle membrane 22.

The needle cannula 12 of the needle assembly is pointed at both sharppointed end 14 and tip 16. The sharp pointed end 14 can penetrate nozzlemembrane 22 when needle hub 20 is moved toward the nozzle membrane 22.The tip 16 of needle cannula 12 is used to administer the medicament,for example intravenously, or intramuscularly through the skin of apatient.

The needle hub 20 of the needle assembly is made of polystyrene and ispreferably secured to needle cannula 12 using an adhesive, such as anepoxy resin. The needle hub 20 can be cylindrical in shape and have afirst section 24 of large diameter and a second section 26 of smalldiameter. The dimensions of large diameter first section 24 and of theinternal diameter of a cylindrical nozzle 18 are selected so that needlehub 20 is frictionally held within the cylindrical nozzle 18, but can bemoved laterally within the nozzle 18 when a force is applied to needlehub 20, as explained below.

The nozzle 18 of the needle assembly can be cylindrical in shape. Aninternal rib 28 is formed between nozzle membrane 22 and needle hub 20to prevent sharp pointed end 14 of the needle cannula 12 from piercingthe closed end of the tube unless a sufficient force is applied. Thedimensions of internal rib 28 and of large diameter first section 24 areselected so that needle hub 20 will not move past rib 28 unless asufficient force is applied to needle hub 20. This structure reduces therisk of unintentional piercing of nozzle membrane 22.

The compression syringe 10 has a protector cap 30, which cooperates withthe nozzle 18 to enclose and protect the needle cannula 12. The open end34 of the protector cap 30 is configured to fit inside the nozzle 18 andpreferably has an external diameter so selected to be snugly held inposition within the nozzle 18. The protector cap 30 is long enough toprevent its closed end 32 from contacting the tip 16 of the needlecannula 12 when the needle cannula 12 is enclosed in the protector cap30 and the nozzle 18. As a result, the protector cap 30 and the nozzle18 keep the needle cannula 12 sterile during storage and shipment of thecompression syringe 10.

The protector cap 30 and the needle hub 20 cooperate with each other toaxially move the needle cannula 12 within the nozzle 18. The internaldiameter of open end 34 of the protector cap 30 is selected so that thesmall diameter second section 26 of needle hub 20 fits snugly within theopen end 34 of the protector cap 30. The external diameter of open end34 of the protector cap 30 is selected so that the protector cap 30 canbe moved laterally within the nozzle 18. The protector cap 30 so formedcan be used as a tool in which the open end 34 of the protector cap 30is pushed against the large diameter first section 24 of the needle hub20. In this way, a sufficient force can be safely applied to the needlehub 20 to force it past internal rib 28. The protector cap 30 thencontinues pushing large diameter first section 24 of needle hub 20 untilsharp pointed end 14 of needle cannula 12 pierces the nozzle membrane22.

The compression syringe 10 also includes a reservoir 46 for storingmedicament and for expelling the medicament into the needle assembly.The reservoir 46 is formed from a pair of flexible sheets 38 a and 38 bof thermoplastic material. Each sheet 38 a, 38 b has a central portion40, an expanded injection neck portion 42, and a substantially flatperipheral portion 44. The peripheral portions 44 of the two sheets 38a, 38 b are opposite and coextensive to each other and are sealedtogether face-to-face to form a reservoir 46. The reservoir 46 can befilled with medicament via a filling neck portion 56 (see FIG. 1) havinga filling port 58 as explained more fully in U.S. Pat. No. 4,955,871.Following the filling step, the filling neck portion 56 of the twoflexible sheets 38 a, 38 b are heated sealed together by a sealingportion or region 57 (see FIG. 2).

To activate the compression syringe 10 of FIGS. 1 to 3, the protectorcap 30 is pushed back towards the needle hub 20 to cause sharp pointedend 14 of the needle cannula 12 to pierce the nozzle membrane 22, thusplacing the needle cannula 12 in fluid communication with the reservoir46. The protector cap 30 is then removed to expose the tip 16 of theneedle cannula 12 for administering an injection to a patient. Toadminister the medicament, the central portion 40, i.e., the flexiblewall of the reservoir 46, is compressed, such as between the thumb andforefinger of the user. After the medicament is administered, the needlecannula 12 is withdrawn from the patient and covered to avoid exposureand possible contamination from the used needle tip 16.

The above described compression syringe 10 is however incompatible witha luer connector and unable to administer the medicament through a luerconnector.

FIGS. 4 and 5 show another conventional luer-type syringe 10′, whichemploys a luer fitting 19 to deliver medicament directly to a luerconnector. Luer-type syringes 10′ are typically sealed by a cap 31,which can be twisted-off to expose the luer channel 21 at the luer tip.Such cap 31 however can be accidentally damaged or removed duringshipping or handling of the luer-type syringes 10′ causing such syringes10′ unfit for their normal use. In addition, as the luer fitting 19 isintended to be directly fit in a sterile luer connector the luer fitting19 or the entire syringe 10′ must be sealed to protect the luer fitting19 from contamination prior to the use of the syringe 10′.

These and other disadvantages can adversely affect the operation of suchluer-type syringes 10.

Accordingly, there is need for an injection device with a luer fittingso as to be directly insertable into a compatible female luer connectorfor administering medicament therethrough. In particular, there is needfor an injection device with a protected luer fitting that is shieldedfrom contamination during the handling of the injection device.

The embodiments below describe an injection device that is sealedagainst leakage through its luer tip of content from the medicamentreservoir. Additionally or alternatively, the male luer fitting of theinjection device is sealed from outside contamination prior to the useof the injection device.

SUMMARY OF THE INVENTION

The present invention relates generally to an injection device fordelivering a dose of medicament by injection and having a shield systemfor preventing contamination of the injection device during itsoperation. For example, the injection device can be a prefilledcompression syringe. The injection device has a syringe body defining acompressible reservoir for containing a dose of medicament. A male luerfitting is provided and has a channel therethrough for conductingcontents of the reservoir and is defined by an outer surface, a base endconnected to the syringe body, and a luer tip at an end of the male luerfitting opposing the base end. A shield cap is arranged on and sealedagainst the male luer fitting at a first position prior to use of theinjection device. The shield cap can be rotated about or moved along anaxis of the male luer fitting during movement from the first position toa second position.

A first seal is provided for sealing the channel at the luer tip of themale luer fitting and preventing leakage therethrough of content fromthe reservoir at least when the shield cap is at the first position. Inone example, the luer tip can be sealed by the first seal in the form ofa membrane closing the channel of the male luer fitting. In such a case,the shield cap can be formed with a sharp tip facing the luer tip whenthe shield cap is in the first position. For example, the sharp tip cancomprise a needle bonded to the shield cap. The sharp tip is capable ofpuncturing or cutting the first seal when the shield cap is moved fromthe first position to the second position.

In another example, the first seal can be in the form of a twist-offtab, which is joined to the luer tip of the male luer fitting by aweakened or frangible joint. The twist-off tab closes the channel in themale luer fitting in the first position. In one example, one end of thetwist-off tab is received in a recess formed in the shield cap when theshield cap is in the first position. The recess defines a shoulder whichcomes into contact with the twist-off tab during movement of the shieldcap from the first position to the second position. The shoulder forcesthe twist-off tab to twist and subsequently break from the make luerfitting, when the shield cap is moved from the intermediate position tothe second position. Upon turning the shield cap from the first positionto the second position, the weakened or frangible joint connecting thetwist-off tab to the luer tip of the male luer fitting breaks and thusreleases the first seal.

The recess in the shield cap can further define a cap flat surfacearranged to retain the twist-off tab by friction fit after the twist-offtab is broken from the male luer fitting. In the alternative, the capflat surface is arranged to retain the twist-off tab when the shield capis moved from the first position to an intermediate position between thefirst and second positions.

Optionally, the injection device comprises an alignment indicatorindicating alignment of the shield cap with the first position relativeto the male luer fitting.

Alternatively, the first seal can be formed by a sealing piece connectedin the shield cap and plugged or seated into the channel of the maleluer fitting at its luer tip when the shield cap is in the firstposition. The sealing piece is removed from the channel, when the shieldcap is released from the male luer fitting.

A second seal is arranged between the shield cap and the male luerfitting for protecting the outer surface and the luer tip of the maleluer fitting from outside contamination when the shield cap is arrangedat the first position. The second seal is formed by a first connectingstructure formed on the male luer fitting between the base end and theluer tip and a second connecting structure formed on the shield cap. Thefirst and second connecting structures interact with each other toprevent inadvertent movement of the shield cap relative to the male luerfitting when the shield cap is arranged at the first position.

The first and second connecting structures comprise ribs and the secondseal is formed by a tortuous path formed by the ribs when the shield capencloses the male luer fitting in the first position. In one example,the first and second connecting structures comprise circumferential ribsor raised rings. In another example, the first and second connectingstructures comprise screw threads, which interlock to form the secondseal.

The injection device further comprises a collar connected to the shieldcap by frangible tabs when the shield cap is in the first position.

The injection device can further comprise a locking piece arrangedproximate the base end of the male luer fitting. The locking piece isconfigured to interact with collar connected to the shield cap byfrangible tabs when the shield cap is in the first position. The lockingpiece retains the collar during movement of the shield cap from thefirst position to the second position and causes the frangible tabs tobreak such that the collar is separated from the shield cap after theshield cap is moved from the first position to the second position. Inone example, the locking piece and the collar comprise complementaryserrated edges.

The shield cap of the injection device is movable relative to the maleluer fitting to the second position from the first position to break oneor both of the first and second seals so that the male luer fitting iscapable of delivering the contents of the reservoir after the shield capis removed from the male luer fitting from the second position. In oneexample, the shield cap is unthreaded during movement from the firstposition to the second position, thereby lifting the first seal from theluer tip.

The injection device of the invention is hence sealed against leakagethrough the luer tip of content from the reservoir when the shield capis in the first position. Additionally or alternatively, the male luerfitting of the injection device is sealed from outside contaminationprior to the use of the injection device.

The present invention also relates to a method of dispensing contents ofa compressible reservoir of an injection device through a male luerfitting connected to the injection device. The method includes placing ashield cap at a first position on the male luer fitting; sealing, with afirst seal, a luer tip preventing leakage therethrough of content fromthe reservoir of the syringe at least when the shield cap is at thefirst position; and sealing an outer surface of the luer tip fromoutside contamination by a second seal formed by first and secondconnecting structures on the male luer fitting and the shield cap,respectively, when the shield cap is arranged at the first position. Forexample, the first seal includes a sealing piece seated in an opening onthe luer tip when the shield cap is in the first position. The secondseal is formed by ribs or circumferential rings arranged on the shieldcap and the male luer fitting. In one example, the step of sealing aluer tip can comprise sealing the luer tip with a twist-off tabconnected to the male luer fitting by a frangible connection.

During use of the injection device, the shield cap on the male luerfitting is moved from a first position to a second position to open atleast the first seal. The shield cap may then be removed from the maleluer fitting so that the contents of the reservoir are capable of beingdispensed.

The shield cap can be either pulled away from or twisted-off the maleluer fitting. Moving the shield cap to the second position can comprisetwisting the shield cap relative to the male luer fitting and moving theshield cap longitudinally relative to the male luer fitting.

In a first example, the shield cap includes a sharp tip facing the firstseal when the shield cap is in the first position. The sharp tip can cutthrough or pierce the first seal during movement of the shield cap fromthe first position to the second position.

In a second example, the method can comprise holding, by the shield cap,the twist-off tab during the step of moving so that the twist-off tabbreaks away from the luer tip during movement of the shield cap from thefirst position to the second position.

In a third example, the second seal is formed by interlocking helicalthreads on the shield cap and the male luer fitting. The step of movingthe shield cap to the second position can comprise twisting the shieldcap relative to the male luer fitting to unthread the interlockingthreads.

In a fourth example, the shield cap includes a collar connected to theshield cap by frangible tabs when the shield cap is in the firstposition. The step of moving the shield cap to the second position canfurther comprise breaking the frangible tabs, wherein the collar remainson the male luer fitting after the step of removing.

These and additional configurations, features, and advantages inconnection with the injection device will become more evident throughthe following detailed description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description is set forth in connection with the attacheddrawing figures, which are not necessarily to scale, emphasis insteadgenerally being placed upon illustrating the principles of theinvention. In the drawing figures and the following detaileddescriptions, wherein similar elements and components are denoted withreference numerals having the same two lower digits throughout theseveral views and redundant descriptions are omitted:

FIG. 1 is an exploded perspective view of a conventional compressionsyringe;

FIG. 2 is a perspective view of the syringe of FIG. 1 in an assembledstate;

FIG. 3 is a longitudinal sectional view of the compression syringe shownin FIG. 2;

FIG. 4 is a plan view of the top of another conventional compressionsyringe in an assembled state;

FIG. 5 is a partial longitudinal sectional view of the luer fitting andthe cap of the compression syringe shown in FIG. 4;

FIG. 6 is a plan view of the top of an assembled injection device shownin an assembled state and formed according to a first embodiment of theinvention;

FIG. 7 is a plan view of the top of the injection device shown in FIG. 6without the shield cap;

FIG. 8 is a longitudinal sectional view of the injection device shown inFIG. 6 and in a first position;

FIG. 9 is a longitudinal sectional view of the injection device shown inFIG. 6 and in a second position;

FIG. 10 is a partial longitudinal sectional view of the second sealformed on the injection device of FIG. 6;

FIG. 11 is a longitudinal sectional view of an alternative shield cap;

FIG. 12 is a perspective view of an injection device formed in anassembled state and according to a second embodiment of the invention;

FIG. 13 is a partial longitudinal sectional view of the injection devicein FIG. 12;

FIGS. 13A and 13B are partial longitudinal sections showing a twist-offtab being joined to and detached from the luer tip of the male luerfitting shown in FIG. 13;

FIG. 14 is a partial perspective view of the injection device shown inFIG. 12 and in a first position;

FIG. 15 is a partial perspective view of the injection device shown inFIG. 12 and in a second position;

FIG. 16 is a partial exploded perspective view of the injection devicein FIG. 12;

FIG. 17 is a perspective view of an injection device formed in anassembled state and according to a third embodiment of the invention;

FIG. 18 is a longitudinal sectional view of the injection device shownin FIG. 17;

FIG. 19 is a plan view of the top of the injection device shown in FIG.17;

FIG. 20 is a side view of the injection device shown in FIG. 17;

FIG. 21 is a front end view of the injection device shown in FIG. 17;

FIG. 22 is a rear end view of the injection device shown in FIG. 17;

FIG. 23 is a partial longitudinal sectional view of the injection deviceshown in FIG. 17 and in a first position;

FIG. 24 is a partial perspective view of the male luer fitting of theinjection device shown in FIG. 17;

FIG. 25 is a perspective view of the shield cap of the injection devicein FIG. 17;

FIG. 26 is a perspective view of a variation of the injection device inthe third embodiment in an assembled state;

FIG. 27 is a partial longitudinal sectional view of the injection devicein FIG. 26;

FIG. 28 is a partial exploded front perspective view of the injectiondevice shown in FIG. 26 before being assembled;

FIG. 29 is a partial perspective view of the injection device shown inFIG. 26 after the shield cap breaks off from the male luer fitting; and

FIG. 30 is a partial exploded rear perspective view of the injectiondevice shown in FIG. 26 before being assembled.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The various injection devices described herein are formed to store adose of medicament and deliver the same by injection. Althoughcompression syringes are shown in the various drawing figures asexamples of the injection devices, the invention is not limited to suchcompression syringes.

FIGS. 6 to 11 illustrate an injection device 110 according to a firstembodiment of the invention. The injection device 110 is shown as acompression syringe including a syringe body 137 defining a reservoir146 for storing medicament. The syringe body 137 is at least partiallycompressible for expelling the medicament into a male luer fitting 150,which will be described in detail below. The reservoir 146 is formedfrom a pair of flexible sheets 138 a and 138 b of thermoplasticmaterial. Each of the sheets 138 a, 138 b can have a central portion140, an expanded injection neck portion 142, and a substantially flatperipheral portion 144. At least a portion of the sheets 138 a, 138 bforming the central portion 140 so that the central portion 140 iscompressible. The peripheral portions 144 of the two sheets 138 a, 138 bare opposite and coextensive to each other and are sealed togetherface-to-face to form a reservoir 146. The reservoir 146 can be filledwith a dosage of medicament via a filling neck portion, during a fillingstep prior to sealing the two flexible sheets 138 a, 138 b together asis known.

The male luer fitting 150 of the injection device 110 has an internalchannel 152 extending from a base end 154 b to a luer tip 154 t of themale luer fitting 150. The internal channel 152 is in fluidcommunication with the reservoir 146 for conducting its contents. Thebase end 154 b of the male luer fitting 150 is sealed to and between thepair of flexible sheets 138 a and 138 b and in fluid communication withthe reservoir 146 via the injection neck portion 142. The male luerfitting 150 can be formed to connect with the reservoir 146 using anyknown or hereafter developed connection.

The male luer fitting 150 has a contact portion 156 extending from theluer tip 154 t toward the base end 154 b. The contact portion 156 isformed to be directly fitted inside a female luer connector (not shown)when administering the medicament through such a female luer connector.In an example shown in FIG. 7, the contact portion 156 has asubstantially cylindrical shape. The contact portion 156 can be taperedtoward the luer tip 154 t resulting in a reduced tip for easy handing ofthe injection device 110 during its assembling and insertion into theluer connector. The taper can be linear or parabolic or have any othercurved shape to facilitate the contact portion 156 to be inserted intoand connected with a corresponding female luer connector.

The male luer fitting 150 can also have a flange portion 158 between thebase end 154 b and the contact portion 156. The flange portion 158 hasan increased radial dimension relative to the remaining portions of themale luer fitting 150 to facilitate its handling. Optionally, thecircumferential surface of the flange portion 158 can be formed withmultiple axial ribs or grooves or knurled or otherwise textured toincrease traction or grip of the male luer fitting 150 or the entireinjection device 110.

The injection device 110 also includes a shield cap 160, which isadapted to fit over at least part of the male luer fitting 150 at afirst position prior to use of the injection device 110. The shield cap160 has a body portion 162 with a closed end 164 c and an open end 164p. In the example shown in FIGS. 6 and 8, said shield cap 160 surroundsand encloses the luer tip 154 t and the contact portion 156 of the maleluer fitting 150 at the first position. In such a first position, theshield cap 160 allows the channel 152 to remain sealed to preserve thecontents in the reservoir 146. Additionally or alternatively, the shieldcap 160, together with additional sealing means described below, shieldsthe contact portion 156 of the male luer fitting 150 from outsidecontamination in said first position.

The shield cap 160 can be moved relatively to the male luer fitting 150from the first position to a second position to release a seal closingthe channel 152 at the luer tip 154 t of the male bier fitting 150, aswill be described in detail below. If desired, the outer surface 166 ofthe shield cap 160 can be formed with multiple axial ribs or grooves orknurled or otherwise textured to increase traction and facilitatehandling of the shield cap 160 or the entire injection device 110.

The injection device 110 can include additional seals to prevent leakagethrough the luer tip 154 of the male luer fitting 150 of content fromthe reservoir 146 in the first position. Additionally or alternatively,such additional seals can prevent contamination of the contact portion156 of the male luer fitting 150 prior to the use of the injectiondevice 110.

As FIGS. 8 and 9 show, a first seal 170 is provided for sealing thechannel 152 of the male luer fitting 150 at its luer tip 154 to preventleakage therethrough of content from said reservoir 146, at least whenthe shield cap 160 is at said first position. In one example, the firstseal 170 can be in the form of a membrane 172 formed at the luer tip 154t to seal the channel 152 inside the male luer fitting 150. Suchmembrane 172 maintains the channel 152 in a closed or sealed state untilthe injection device 110 is activated to administer the medicament.

In one embodiment, a piercing element 174, such as a needle or a sharptip, is used to activate the injection device 110. As FIGS. 8 and 9show, the piercing element 174 is formed at the closed end 164 c of theshield cap 160. The piecing element 174 has a sharp tip oriented towardand aligned with the first seal 170 in an axial direction. When theshield cap 160 is in the first position as is shown in FIG. 8, thepiecing element 174 remains in a position without disrupting the firstseal 170, such as membrane 172. In one example shown in FIG. 8, thesharp tip of the piercing element 174 faces said luer tip 154 t whensaid shield cap 160 is in said first position. When the shield cap 160is moved from the first position to the second position as is shown inFIG. 9, the piercing element 174 is urged into the first seal 170 untilthe first seal 170 is pierced or broken to allow the release of themedicament contained in the reservoir 146.

The piercing element 174 can be formed in various ways. In the examplesshown in FIGS. 8 and 9, the piercing element 174 can be separatelyformed as a needle tip fixed to the closed end 164 c of the shield cap160 by various means, such as bonding and adhesion. In another exampleshown in FIG. 11, the piercing element 174 can be integrally formed withthe shield cap 160, such as through a molding process. Additionally oralternatively, the piercing element 174 can be made of or reinforcedwith various materials, such as metal or plastics.

The second seal 180 is formed between said male luer fitting 150 and theshield cap 160 when the shield cap 160 is arranged at the firstposition. The second seal 180 protects the contacting portion 156 andthe luer tip 154 t of said male luer fitting 150 from outsidecontamination. In one example best shown in FIG. 10, the second seal 180includes first and second connecting structures 182, 184 formed on themale luer fitting 150 and the shield cap 160, respectively. For example,the first connecting structure 182, such as circumferential ribs orraised rings 182 a, 182 b, can be arranged on said male luer fitting 150between said base end 154 b and said luer tip 154 t. The secondconnecting structure 184, such as an internal circumferential rib ofraised ring, can be formed inside the shield cap 160. The interlockingof the first and second connecting structures 182, 184 forms a barrierbetween the male luer fitting 150 and the shield cap 160 and preventsthe contact portion 156 of the male luer fitting from beingcontaminated.

Additionally or alternatively, the second connecting structure 184interacts with the first connecting structure 182 to prevent inadvertentmovement of the shield cap 160 relative to said male luer fitting 150when said shield cap 160 is arranged at said first position. In oneexample, the circumferential ridge 184 on the shield cap 160 is fitbetween the circumferential ribs 182 a, 182 b on said male luer fitting150 when the shield cap 160 is in the first position. In such a case,the circumferential rib 182 a closer to the base end 154 b of the maleluer fitting 150 can prevent the shield cap 160 from accidentally movinginto the second position and, consequently, damaging the membrane 172prior to the normal use of the injection device 110. On the other hand,the circumferential ridge 182 b closer to the luer tip 154 t of the maleluer fitting 150 can prevent the shield cap 160 from being accidentallypulled away from the male luer fitting 150 and, consequently, subjectits contact portion 156 to contamination.

The injection device 110 can be assembled by placing the shield cap 160on the contact portion 156 of the male luer fitting 150 in the firstposition, as is shown in FIG. 8. When doing so, the operator brings themale luer fitting 150 and the shield cap 160 toward each other and pullsthe shield cap 160 over the luer tip 154 t and then the contact portion156 of the male luer fitting 150. When the circumferential rib 184 onthe shield cap 160 comes in contact with the circumferential rib 182 bon the male luer fitting 150, the operator applies a gentle force tourge the circumferential rib 184 to pass the circumferential rib 182 b.The circumferential rib 184 on the shield cap 160 thus falls between thetwo circumferential ribs 182 a, 182 b on said male luer fitting 150 andbring the shield cap 160 into the first position.

A description of exemplary usage of the injection device 110 of thepresent invention is provided below. It should be understood by a personof ordinary skill in the art that the following description is providedas an illustrative and non-limiting example.

When activating the injection device 110, an operator moves the shieldcap 160 further onto the male luer fitting 150 from the first positiontoward the second position. The movement urges the circumferential rib184 on the shield cap 160 to pass the circumferential rib 182 a on themale luer fitting until the piercing element 174 is forced into themembrane 172 to pierce or break through the same at the second position.The shield cap 160 can then be removed from the male luer fitting 150from said second position to expose the contact portion 156 and luer tip154 t. The male luer fitting is then inserted in a female luer connector(not shown). The operator then digitally compresses the reservoir 146,for example, between a thumb and a forefinger, to deliver the contentsof the reservoir 146.

The used shield cap 160, together with the piercing element 174 fixed tothe closed end 164 c of the shield cap 160, can then be either disposedor sterilized for further use. In one example, the used shield cap 160can be reassembled with the used syringe body 137 and disposed together.In another example, the used shield cap 160 can be reassembled with theused syringe body 137 and stored for a future use of the remaining drug.In a further example, the used shield cap 160 can be sterilized andassembled with another new syringe body 137.

The first and second connecting structure 182, 184 and seals 170, 180may alternatively be formed in various other manners as described inadditional embodiments below.

FIGS. 12 to 16 illustrate an injection device 210 formed according to asecond embodiment of the invention. In this embodiment, the syringe body237, the male luer fitting 250, and the shield cap 260 are similarlyformed to their respective counterparts 137, 150, and 160 described inthe first embodiment. Only the differences between the first and secondembodiments are described in details below.

As is shown in FIGS. 13 and 16, the first seal 270 in this embodiment isin the form of a twist-off tab 272 connected to the luer tip 254 to sealthe channel 252 in the male luer fitting 250. As is best shown in FIG.13A, the twist-off tab 272 is joined to the luer tip 254 through aweakened or frangible portion 272 a. As is described in details belowand shown in FIG. 13B, the weakened or frangible portion 272 a can besevered or broken off when activating the injection device 210 toadminister the medicament contained in the reservoir 246.

To facilitate the removal of the twist-off tab 272 when activating theinjection device 210, a clamping element 274 is provided and in the forman internal recess in the closed end 264 c of the shield cap 260. As isshown in FIGS. 14 and 15, the recess 274 has a contoured circumferenceincluding a pair of radially opposite first walls 274 f formed toaccommodate the twist-off tab 272 therebetween. The radially oppositefirst walls 274 f are spaced apart so that they do not interfere withthe twist-off tab 272 after such tab 272 is placed between the firstwalls 274 f in a first position.

The contoured circumference of the recess 274 also includes a pair ofradially opposite clamping walls 274 p circumferentially adjacent thefirst wall 274 f in a circumferential direction, and an additional pairof radially opposite clamping walls 274 n circumferentially adjacent thefirst wall 274 f in an opposite circumferential direction. Each pair ofthe radially opposite clamping walls 274 p, 274 n are spaced from eachother for a distance less than the larger radial dimension of thetwist-off tab 272. When the shield cap 260 is rotated in relation to themale luer fitting 250 to align with the adjacent radially oppositeclamping walls 274 p, 274 n, the twist-off tab 272 on the male luerfitting 250 is radially clamped between one of the pairs of radiallyopposite clamping walls 274 p, 274 n.

Additionally, one or more shoulders 274 s are formed on the contouredcircumference and extend radially towards each other. The shoulders 274s can serve as a severance means for the twist-off tab 272 when theshield cap 260 moves from the first position to a second position. Inone example, when the shield cap 260 continues to rotate in relation tothe male luer fitting 250, the twist-off tab 272 abuts the shoulders 274s and is forced to rotate in relation to the mail luer fitting 250 bythe shoulders 274 s until the weakened or frangible portion 272 abreaks. The severed twist-off tab 272 remains in the recess 274 held bythe radially opposite clamping walls 274 p, 274 n and can be removedfrom the male luer fitting 250 together with the shield cap 260.

As is shown in FIG. 16, the second seal 280 can be in the form of one ormore ribs, rings, bumps, or other protrusions formed on the male luerfitting 250 between said base end 254 b and said luer tip 254 t. In oneexample, the second seal 280 includes one or more tortuous path ribs 282adapted to frictionally engage the interior wall of the shield cap 260,thereby providing a seal between the male luer fitting 250 and theshield cap 260 and preventing alien matter from entering the shield cap260 and contaminating the contact portion 256 of the male luer fitting250. As a result, the shield cap 260 is held in place on the male luerfitting 250 in the first position. As one skilled in the willappreciate, the tortuous path ribs 282 can alternatively or additionallybe formed on the interior wall of the shield cap 260 to frictionallyengage the male luer fitting 250.

When assembling the injection device 210, the male luer fitting 250 andthe shield cap 260 are brought toward and aligned with each other. Forexample, the twist-off tab 272 on the male luer fitting 250 is to bealigned with the radially opposite first walls 274 f in the closed end264 c of the shield cap 260. To facilitate the alignment, the male luerfitting 250 and the shield cap 260 can be provided with alignment marks,such as orientation lines 276 m, 276 s, respectively. After the shieldcap 260 fully fits over the contact portion 256 on the male luer fitting250 in the first position, the twist-off tab 272 is positioned betweenthe radially opposite first walls 274 f in the closed end 264 c of theshield cap 260.

A description of exemplary usage of the injection device 210 of thepresent invention is provided below. It should be understood by a personof ordinary skill in the art that the following description is providedas an illustrative and non-limiting example.

To activate the injection device 210, the shield cap 260 is rotatedrelatively to the male luer fitting 250 either clockwise orcounterclockwise. Such relative rotation drives the twist-off tab 272 inbetween a pair of the radially opposite clamping walls 274 p, 274 n inthe shield cap 260. As a result, the twist-off tab 272 is squeezed orpinched by the radially opposite clamping walls 274 p, 274 and heldthereby. The shield cap 260 is then further rotated in relation to themale luer fitting 250 and the shoulders 274 s carry the twist-off tab272 along in the rotation until the weakened or frangible portion 272 abreaks. The shield cap 260, together with the twist-off tab 272 held bythe radially opposite clamping walls 274 p, 274 n, is then removed fromthe male luer fitting 250 to expose the contact portion 256 and luer tip254 t. The male luer fitting 250 is then inserted in a female luerconnector (not shown). Once inserted the operator squeezes the reservoir246 to administer the medicament.

The first and second seals 270, 280 can alternatively be formed by thevarious connecting structures and seals described in the otherembodiments of the present application.

FIGS. 17 to 25 illustrate an injection device 310 formed according to athird embodiment of the invention. In this embodiment, the syringe body337, the male luer fitting 350, and the shield cap 360 are similarlyformed to their respective counterparts 137, 150, and 160 described inthe first embodiment. Only the differences between the third embodimentand the previous embodiments are described in details below.

A first seal 370 is formed at a closed end 364 c inside the shield cap360. The first seal 370 is in the form of a protrusion toward andaligned with a channel 352 in the male luer fitting 350 in an axialdirection. In the first position, as is shown in FIGS. 18 and 23, thefirst seal 370 is plugged or seated in the channel 352 at the luer tip354 t of the male luer fitting 350. The first seal 370 prevents leakageof medicament from the syringe body 337. As is described below, when theshield cap 360 is moved from the first position to the second position,the first seal 370 is removed or unseated from inside the channel 352 toallow the release of the medicament contained in the reservoir 346.

The second seal 380 in this embodiment can comprise matching helicalthreads 382, 384 formed on the respective male luer fitting 350 andshield cap 360. In the example shown in FIG. 23, the shield cap 360 hasan enlarged open end 364, inside which the thread 384 is formed. Thematching threads 382, 384 are capable of engaging with each other toseal the contact portion 356 of the male luer fitting 350 from outsidecontamination. Additionally or alternatively, the second seal 380 canprevent the first seal 370 from being accidentally pulled out from thechannel 352 and thus at least partially operate as a fastening means forthe first seal 370.

As FIG. 23 shows, the injection device 310 can be provided with afastener 390 to assist in retaining the shield cap 360 in the firstposition and prevent such shield cap 360 from disengaging with the maleluer fitting 350 caused by either operational error or environmentaldisturbance. In one example, the male luer fitting 350 is provided witha locking structure 392 m, such as serrated edges, as best shown in FIG.24. The shield cap 360 is formed with a matching locking structure 392s, e.g., serrated edges, which, once matched with the locking structure392 m on the male luer fitting 350, prevent unintentional rotation ofthe shield cap 360 relative to the male luer fitting 350. As a result,the risk of unintended disengagement of the male luer fitting 350 andthe shield cap 360 can be reduced.

If desired, one or more additional seals can be provided in thisembodiment to enhance the sealing of the contact portion 356 of the maleluer fitting 350. In one example as is shown in FIG. 23, the male luerfitting 350 is formed with a circumferential shoulder 386 m to contactor otherwise engage with a corresponding internal circumferentialshoulder 386 s formed inside the shield cap 360. Such additional seals386 m, 386 s can further block alien matter passing through the matchinglocking structures or serrated edges 392 m, 392 s and/or the matchingthreads 382, 384 between the male luer fitting 350 and the shield cap360.

To assemble the injection device 310, the shield cap 360 is screwed orthreaded onto the male luer fitting 350, such as in a clockwisedirection, so that the matching threads 382, 384 are engaged with andsealed against each other to protect the contacting portion 356 againstoutside contamination. In the meantime, the first seal 370 on the closedend 364 c inside the shield cap 360 is plugged or seated into thechannel 352 at the luer tip 354 t of the male luer fitting 350 andthereby seals the medicament inside the reservoir 346. The shield cap360 is further urged onto the male luer fitting 350 until the fastener390 is engaged. For example, the matching locking structures 392 m, 392s can be engaged with each other to retain the first and second seals370, 380 in the first position without being disturbed by unintentionalforces acting on the injection device 310.

A description of exemplary usage of the injection device 310 of thepresent invention is provided below. It should be understood by a personof ordinary skill in the art that the following description is providedas an illustrative and non-limiting example.

To activate the injection device 310, an operator twists the shield cap360 in the counterclockwise direction to disengage the fastener 390. Forexample, the operator can twist the shield cap 360 to cause the serratedthreads 392 m, 392 s to override and disengage from each other. Theoperator continues to twist or rotate the shield cap 360 in thecounterclockwise direction until the matching threads 382, 384 disengagefrom each other. At the same time, the first seal 370 is axially pulledout from the channel 352 in the male luer fitting 350 to activate thereservoir 346. When the first and second seals 370, 380 are released,the shield cap 360, together with the attached first seal 370 is removedfrom the contact portion 356 of the male luer fitting 350 to expose thecontact portion 356 and the luer tip 354 t. The contaminant free maleluer fitting 350 of the injection device 310 is then fitted directly ina female luer connector (not shown). To deliver the medicament, theoperator squeezes the reservoir 346.

The first and second connecting structure 382, 384 and seals 370, 380and the fastener 390 can alternatively be formed in accordance with theconnecting structures and seals described in the other embodiments ofthe present application.

FIGS. 26 to 30 illustrate an injection device 410 formed as a variationof injection device 310 described above. In the injection device 410,the syringe body 437, the male luer fitting 450, and the shield cap 460are similarly formed to their respective counterparts 137, 150, and 160described in the first embodiment. In addition, the first seal 470 inthe injection device 410 is formed similarly to the first seal 370described in the above embodiment. The differences between the injectiondevice 410 and the previous embodiments are described in details below.

The second seal 480 in the injection device 410 can comprise matchingthreads 482, 484 formed on the respective male luer fitting 450 andshield cap 460. The second seal 480 is formed between said male luerfitting 450 and said shield cap 460 in the first position to preventalien matter to pass through and contaminate the contacting portion 456of the luer tip 454 t of said male luer fitting 450. In the exampleshown in FIG. 27, the first connecting structure 482 can be in the formof at least one circumferential rib or spiral thread 482 a, 482 barranged on said male luer fitting 450 between said base end 454 b andsaid luer tip 454 t. The second connecting structure 484 can be in theform of an internal circumferential rib or spiral thread 484 a formedinside the shield cap 460 at its open end 464 p. The first and secondconnecting structures 482 a, 482 b, 484 can interlock with each other toseal the interior of the shield cap 460 and thus seal the contactportion 456 of the male luer fitting 450 from contamination.

In addition, a fastener 490 can be provided in the injection device 410to retain the first and second seals 470, 480 in the first position. Inone example, the fastener 490 is in the form of a tamper seal, which caninclude a first collar member 494 connected to the open end 464 p of theshield cap 460 through a number of tamper-proof tabs 496. The collarmember 494 is formed to fit onto the circumferential surface of theflange 458 on the male luer fitting 450. The interface of the collarmember 494 and the flange 458 can be adapted to cooperate with eachother allowing only a one-way relative rotation therebetween. Forexample, the interface of the collar member 494 and the flange 458 canbe a one-way locking thread 492 m, 492 s to allow the shield cap 460 tobe twisted onto the male luer fitting 450 and prevent the shield cap 460from rotating in an opposite direction, thereby loosened from the maleluer fitting 450.

If desired, one or more of the circumferential surfaces of the shieldcap 460 or collar 494 can be provided with additional traction and grip,such as a knurled grip, to the operator when handling the injectiondevice 410. Additional traction member, such as longitudinal ribs orgrooves can be additionally or alternatively provided for the samepurpose.

To assemble the injection device 410, the shield cap 460 is screwed ontothe male luer fitting 450, such as in a clockwise direction, so that thematching threads 482, 484 are engaged with and sealed against each otherto protect the contacting portion 456 against outside contamination. Inthe meantime, the first seal 470 on the closed end 464 c inside theshield cap 460 is plugged or seated into the channel 452 at the luer tip454 t of the male luer fitting 450 to thereby seal the medicament insidethe reservoir 446. The shield cap 460 is then further screwed onto themale luer fitting 450 until the fastener 490 is engaged. For example,the matching locking threads 492 m, 492 s are engaged with each other toprevent the first and second seals 470, 480 from departing from thefirst position. The tamper-proof tabs 496 will break to indicateunintended activation of the injection device 410.

A description of exemplary usage of the injection device 410 of thepresent invention is provided below. It should be understood by a personof ordinary skill in the art that the following description is providedas an illustrative and non-limiting example.

To activate the injection device 410, an operator first inspects thetamper-proof tabs 496 to ensure that they have not been broken. Theshield cap 460 is then twisted in the counterclockwise direction todisengage the fastener 490. For example, the operator can twist theshield cap 460 to break the tamper-proof tabs 496, as is shown in FIG.29. The shield cap 460 can then be removed from the contact portion 456of the male luer fitting 450, while pulling or unseating the first seal470 from the channel 452 of the male luer fitting 450. The male luerfitting 450 is then fitted directly in a female luer connector (notshown). The medicament is then delivered by the operator squeezing orcompressing the reservoir 446.

The first and second connecting structure 482, 484 and seals 470, 480and the fastener 490 can alternatively be formed by the connectingstructures and seals disclosed by the above embodiments.

Thus, while there have shown and described and pointed out fundamentalnovel features of the invention as applied to a preferred embodimentthereof, it will be understood that various omissions and substitutionsand changes in the form and details of the devices illustrated, and intheir operation, may be made by those skilled in the art withoutdeparting from the spirit of the invention. For example, it is expresslyintended that all combinations of those elements which performsubstantially the same function in substantially the same way to achievethe same results are within the scope of the invention. Moreover, itshould be recognized that structures and/or elements shown and/ordescribed in connection with any disclosed form or embodiment of theinvention may be incorporated in any other disclosed or described orsuggested form or embodiment as a general matter of design choice. It isthe intention, therefore, to be limited only as indicated by the scopeof the claims appended hereto.

The invention claimed is:
 1. An injection device with a luer fitting,the injection device comprising: a compressible syringe body comprisingtwo flexible sheets defining a reservoir; a male luer fitting that issubstantially cylindrical having a tapered outer surface, a base end anda luer tip at an end of said male luer fitting opposing said base end,said male luer fitting provided as a separate component from the syringebody, said base end connected to and sealed within said flexible sheets,said male luer fitting having a channel therethrough for conductingcontents of the reservoir; a first connecting structure arranged on saidtapered outer surface of the male luer fitting between said base end andsaid luer tip; a shield cap having a generally cylindrical shapedportion arranged on the male luer fitting at a first position relativeto said male luer fitting prior to use of the injection device, saidshield cap having a second connecting structure on an inner surface ofits generally cylindrical shaped portion and interacting with said firstconnecting structure to prevent inadvertent movement of said shield caprelative to said male luer fitting when said shield cap is arranged atsaid first position; a first seal comprising a pierceable membranesealing said channel at said luer tip and preventing leakagetherethrough of content from said reservoir at least when the shield capis at said first position; and a second seal between said shield cap andsaid male luer fitting sealing the tapered outer surface and the luertip of said male luer fitting from outside contamination, said secondseal formed by said first and second connecting structures when theshield cap is arranged at the first position, wherein said shield cap ismovable relative to said male luer fitting to a second position fromsaid first position, said first seal being pierced by movement of saidshield cap from said first position to said second position, whereinsaid first and second connecting structures each comprise at least onecircumferential rib or raised ring.
 2. The injection device of claim 1,wherein said shield cap is removable from said male luer fitting fromsaid second position, said male luer fitting being capable of deliveringthe contents of the reservoir after said shield cap is removed from saidmale luer fitting from said second position.
 3. The injection device ofclaim 1, wherein said shield cap comprises a sharp tip facing said luertip when said shield cap is in said first position.
 4. The injectiondevice of claim 3, wherein said sharp tip punctures or cuts said firstseal when said shield cap is moved from said first position to saidsecond position.
 5. The injection device of claim 3, wherein said sharptip comprises a needle bonded to said shield cap.
 6. A method ofdispensing contents of a compressible reservoir of an injection devicethrough a male luer fitting that is substantially cylindrical having atapered outer surface connected to the injection device, said methodcomprising: sealing a base end of said substantially cylindrical maleluer fitting within two flexible sheets of a syringe body of theinjection device; placing a shield cap at a first position on said maleluer fitting; sealing, with a first seal, a luer tip preventing leakagetherethrough of content from the reservoir of the syringe body at leastwhen the shield cap is at the first position; sealing, with a secondseal, the tapered outer surface of the luer tip from outsidecontamination by a second seal formed by first and second connectingstructures on the tapered outer surface of the male luer fitting and aninner surface of the shield cap, respectively, when the shield cap isarranged at the first position; moving the shield cap on the male luerfitting from a first position to a second position to open at least thefirst seal; and removing the shield cap from the second position,whereby the contents of the reservoir are capable of being dispensedafter the shield cap is removed from the second position, wherein thesecond seal is formed by at least one rib or circumferential ringarranged on each of the shield cap and the male luer fitting.
 7. Themethod of claim 6, wherein the shield cap includes a sharp tip facingthe first seal when the shield cap is in the first position.
 8. Themethod of claim 7, wherein the sharp tip cuts through or pierces thefirst seal during movement of the shield cap from the first position tothe second position.
 9. The method of claim 6, wherein the step ofmoving comprises moving the shield cap longitudinally relative to themale luer fitting.